| Value | Category | Cases | |
|---|---|---|---|
| 1 | less than one year | 22894 |
4.4%
|
| 2 | one to three years | 83300 |
15.9%
|
| 3 | more than three years | 417581 |
79.7%
|
| 4 | not known | 0 |
0%
|